Site News  |   Monitor Keywords  |   Monitor Archive  |   Organizer  |   Account Info  |

Implant

Implant description/claims

The present invention relates to an implant which can be fitted in an implantation site in a hole formed in a jaw bone, where the implant is exposed to an impinging force or impinging forces. The implant comprises one or more peripherally extending surfaces which are arranged at its upper/outer portion and which can be placed against the jaw bone and soft tissue at the outlet opening of the hole.

The present invention is based, inter alia, on the concept that osteoconduction can be increased with a certain type of groove or recess in the surface. Reference is made in this connection to WO 97/05238 (Boyde) and to the patent application SE 03.03322-2 filed by the Applicant of the present patent application.

When fitting implants of the type in question, it is important to be able to achieve excellent osteoconduction between the jaw bone in question and the implant and to avoid bone absorption, even marginal bone absorption, during the stages of implantation and incorporation. It is also important that the implant is able to resist the force or forces which impinge on the implant in a principal direction. An inclination of the implant, for example because of the jaw bone situation, must, not give rise to movements between implant and jaw bone which prevent a good implantation result. The same applies when the implant supports a tooth replacement in a position which, for example during chewing movements, means that the principal directions of the force or forces are inclined in relation to the longitudinal direction of the implant, which can result in disadvantageous forces acting on the implant and can cause a tendency for the implant to loosen.

The main object of the present invention is, among other things, to solve this problem and it proposes a pattern arrangement of grooves and/or recesses which, in addition to the known osteoconduction of the grooves, also makes the implant resistant to inclinations between the principal direction of an impinging force or impinging forces and the longitudinal direction of the implant.

The increased resistance to forces directed at an incline in relation to the implant must also be such as to ensure that bacteria and/or organisms which tend to cause inflammation do not penetrate from the implant's upper/outer parts (oral cavity) to the deeper-lying or lower parts of the implant. The invention also solves this problem.

The feature that can principally be regarded as characterizing an implant according to the invention is that each surface is provided with a pattern of grooves and/or recesses and that some, for example 20% or more, of the grooves and/or recesses are arranged so that, in the implanted position, they extend substantially at right angles in relation to said force or forces when these latter assume a principal direction or principal directions differing from the longitudinal direction of the implant.

In further developments of the inventive concept, the grooves and/or recesses are closed, which means here that there is no connection between the upper and lower parts of the implant portion in question and that, in this way, passage of bacteria and/or organisms from the upper to the lower parts of the implant is prevented. In a preferred embodiment, the recesses are chosen in the range of 50-100 μm and have groove or recess depths in the range of 100-150 μm. In the case where the implant has an internal socket for a tool, which causes different material thicknesses at the upper parts of the implant, the pattern arrangement is provided only at those parts of the portion having the greater material thicknesses. Different pattern arrangements can be provided. Further developments of the inventive concept are set out, inter alia, in the attached dependent claims.

The above goes against the prevailing views in the dental field by proposing that the surface will be patterned with grooves/recesses. Normally, the aim is for the surface at the outlet opening of the hole to be polished so as to make it easier to keep the surface clean from bacteria and/or organisms of a nature tending to cause inflammation. Such polishing, however, counters said osteoconduction function and makes integration between the surface material of the implant and the jaw bone difficult. The osteoconduction function of the grooves improves bone incorporation, and arranging the grooves in the manner proposed according to the invention counteracts microscopic movements and shearing stresses in the already incorporated bone for the purpose of maintaining the bone level and of preventing bone absorption. Methods known per se can be used to produce the groove and recess arrangements. Thus, it may be possible to use mechanical working, for example turning, milling or engraving. It is also known per se to produce the groove and/of recess arrangement by laser treatment of the surface. Different implants can be provided with different patterns to meet different implantation situations, for example different tooth functions, implant positions in the dentine, etc. Implants with different patterns can thus be made available on the market to provide choice to the specialists concerned.

A presently proposed embodiment of an arrangement having the features characteristic of the invention will be described below with reference to the attached drawings, in which:

FIG. 1 is a diagrammatic vertical cross section through an implantation in the jaw bone where forces acting on the implant have directions/principal directions differing from the longitudinal direction of the implant,

FIG. 2 is a diagrammatic vertical cross section through an implant which is inclined in the implantation site in the jaw bone, with the result that a force with a vertical direction of action differs from the longitudinal extent of the implant,

FIG. 3 is an enlarged vertical cross section through a type of groove or recess which contributes to excellent osteoconduction,

FIG. 4 is a vertical view of the closed groove or recess arrangement in which bacteria are prevented from moving from the upper parts to the lower parts,

FIG. 5 is a side view of a first pattern arrangement, developed in the plane of the figure,

FIG. 6 is a perspective view, obliquely from above, showing parts of an implant with a number of different pattern arrangements, and

FIG. 7 is a perspective view, obliquely from above, showing parts of two other types of implants with a number of different pattern arrangements.

In FIG. 1, a jaw bone is shown diagrammatically by reference number 1. The jaw bone comprises a soft tissue part 2 and, lying under this, a bone part consisting of cortical bone 3a and spongy bone 3b. The jaw bone is provided with a hole 4. An implant 5 is fitted in the hole. The hole can have an internal thread 4a, and the implant is provided with an external thread 5a, by means of which the implant can be screwed into the hole in a manner known per se. The implant is provided with an upper or outer portion 5b which, when the implant is in position in the jaw bone, can be regarded as being situated in or surrounded by the soft tissue 2. Said portion is also arranged at the outlet opening 4b from the hole 4 to the oral cavity, which is indicated symbolically by 6. The implant is intended to support a prosthesis indicated symbolically by reference number 7. The upper portion 5b of the implant is provided with a pattern 8 of grooves and/or recesses. In accordance with the concept of the invention, the grooves and/or recesses in the pattern are arranged such that some of the grooves and/or recesses, for example 20% or more, will be substantially at right angles with respect to the forces acting on the implant when said implant is in the implanted position. Examples of impinging forces and their directions are indicated by F1 and F2. On account of the situation in the oral cavity, the prosthesis type, implant position, etc., the forces F1 and/or F2 can have principal directions differing from the longitudinal axis 5c of the implant. These differences have been defined in FIG. 1 with the aid of angles α and β. Each angle in cross section thus gives the difference between the respective direction of each impinging force.

• Provisional Patent
• Utility Patent

• What Is a Patent?
• What Is a Trademark or Servicemark?
• What Is a Copyright?
• Patent Laws